I'd like to know the difference between convenience food, ready-made food and ready food. I'm not sure, but I thought they are all interchangeable. I can warm them up in the microwave and eat instantly. Is there any difference between these three? And some people say "ready food" and some say "ready-made food". Are they refering to the same thing?
In the UK we would say Ready Meal not Ready Food. The dictionaries I have consulted include Ready Meal and not Ready Food.
Supermarkets will have a section labelled Ready Meals. These are complete meals (meat, sauce vegetables, starches) in one package, already cooked, and now displayed in chilled cabinets, not frozen. The consumer will take them home and reheat in oven or Microwave.
Convenience Foods are foods that are not necessarily already cooked but which can be prepared very quickly. For example canned foods, frozen vegetables or packets of soup noodles. As a generic term it can cover complete frozen meals, but also includes other quickly-prepared foods that do not in themselves constitute a complete meal, but often can be combined together to make something very quickly. Many UK households will have quite a few such convenience foods to hand.
Takeaway Meals are bought hot, perhaps delivered to the door, and consumed immediately.
Fast Food is bought on the premises of the vendor, and usually consumed there. It's fast in that it's not usually cooked to order. Examples: chains such as KFC, McDonalds, Subway. It is interesting that we don't say Fast Meals even though a complete meal is being provided; I have no explanation for why this is so.
In general usage
basically have the same meaning, and describe categories of food-types that have been preprepared and are ready for consumption or usage.
ready-made pie filling
"Ready foods" is also the name of a US food processing company here
And also the name of a UK food processing company here
is a broad category of foods which include ready and ready-made foods.
All three terms carry an implied meaning that the processed food is usually not prepared by the person consuming it.
These should not be confused with "meal, ready-to-eat" (MRE) which is a military term for rations.